ETA PRIME tries to answer that question (while we’re revisiting our initial rating) with some benchmarking courtesy of the Windows drivers Valve released earlier this month. As Videocardz points out, on this unit with 64GB of RAM, the results were pretty close across the three games tested, with SteamOS winning in 1080p across Cyberpunk 2077, Shadow of the Tomb Raider, and Horizon Zero Dawn, but Windows moving a couple of frames per second ahead at 4K rendering.